Electronic mail recipients are increasingly subjected to unsolicited mass mailings (spam). As automated approaches to sending spam began to emerge, software tools were written to counter the growing rate of spam, with the goal of saving companies huge amounts of bandwidth, server resources, and time spent on abuse management. The goal of many anti-spammer tools is to flag spam email. These anti-spammer tools facilitate the detection and classification of unsolicited emails (spam) in an incoming stream of e-mail messages. For example, some software anti-spam applications use heuristic filtering intended to identify specific characteristics of spam. Heuristic filtering may be used to flag incoming email as legitimate or spam. Other systems prevent spam by setting up filters based on statistical filtering which involves measuring probability. For example the tool POPFile uses Bayesian filtering based on word counts. Other tools, for example, TarProxy use existing filters to make decisions on how an email should be delivered.
As discussed above, existing systems tackle the issue of incoming spam. However, more and more applications are being configured to send or facilitate sending of automatic messages, triggered by user-generated events. Thus, a need arises for preventing abuse (i.e., spam) of an application or system that is configured to send information through automatic messages or notifications. For example, presently, many users use distributed computing (i.e., cloud computing) to share files such as documents or images. An application that administers the sharing of files using distributed computing allows a user to designate a file to be viewed or downloaded. A notification is usually sent to other users (i.e., via email) with information that the file is ready to be viewed or downloaded. This notification may be an automatic electronic message that is created and sent once the user-generated event of designating the file to be shared is completed. The creation and sending of the automatic message may be abused as it can be hijacked to disseminate spam. This is a problem because an application that is abused in this way may be blacklisted by mail service providers. Thus if blacklisted, any emails sent by that application are blocked, preventing legitimate emails from the application from reaching the intended recipients. Worse yet, all applications hosted within a certain domain (which could be all or significant applications administered by a company) may be blacklisted by a mail service if spam is detected as originating from within that domain, thus hindering the normal operations of that company.